Flotation apparatus



Nova 3% 9 1926.

. J. c. M mTosH FLOTATION APPARATUS 1925 3 Sheets-Sheet 2 Filed Nov. 13

arvv V min wna w lllu lllu- INVENTOR Johnfilviacl nta h #6 ATTORNEY I Nov. 30 1926.

J. C. M INTOSH FLOIIAT I ON APPARATU 5 Filed Nov. 13, 1925 lmll lmmw- 5 Sheets-Sheet 5 INVTENTOR John, C. Maclnioh; Y WM ATTORNEY Patented Nov. 39, 1926.

JOHN C. MAGIN'TOSH, OF DOUGLAS, ARIZONA, ASSIGNGR, BY DIRECT AND MESNE AS- SIGNMENTS, TO THE GENERAL ENGINEERING COMPANY, A CORPORATION OF UTAH.

FLOTATION APPARATUS.

My invention relates to improvements in apparatus for the concentration of the values from ores or other substances by what is commonly known as the flotation process,

in which the ores or other substances are subjected to aeration in an aqueous separating medium in the presence of suitable agents for the formation of a froth containing the valuable portions of said ores or other substances, and thereby separating said values from the barren or rocky constituents thereof.

The object of the presentinvention is to provide certain improvements in apparatus for practising the method of concentration of the kind referred to. V

The principle of operation and novel features of the invention will be better understood from the following description taken in conjunction with the accompanying drawing illustrating one embodiment of this invention.

In this drawing:

Fig. 1 is a longitudinal sectional elevation of the flotation cell taken on lines CC, Fig. 3. I

Fig. 2 is a plan view of the flotation cell.

Fig. 3 is a transverse section of the flotation cell taken on line A.A, Fig. 2.

Fig. 4 is a transverse section of the flotation cell taken on line BB, Fig. 2.

Fig. 5 is a longitudinal section of the rotor taken on line DD, Fig. 6.

Fig. 6 is a transverse section of the rotor taken on line E-E, Fig. 5.

In Figs. 1 to 4 inclusive, 1 represents the enclosing cellor chamber. Means for the introduction of the feed pulp is shown at 2, Figs. 2 and 4. Means for the removal of tailing is indicated in Figs. 3 and 4, in which 3 is an adjustable weir, 4 is a tailing discharge for the pulp containing the finer particles, and 5 is a bushing provided for the discharge of the pulp containing the coarser particles.

The concentrate launder is shown at 6, and the froth concentrate discharge lip at 7 in Figs. 3 and 4. The height of the concentrat-e overflow lip may be varied as desired by meansof an adiustable froth control weir or lip. actuated by a hand wheel as shown at 9, Fig. 3, or by the more simple means of separately removable longitudinal strips as indicated at 10, Fig. 4.

The rotor or drum forms an essential part of this invention. Its place in the assembled apparatus is shown at 11 in Figs. 1 to 4 inclusive. The inside bottom of the cell is preferably made to conform rather closely to the curved surface described by the outside portion of the rotor.

The details of the rotor are shown in Figs. 5 and 6. Each end of the hollow per forated pipe 12 is threaded into the inner end of the hub of the combined flange and hub 13, at each. end of the rotor, and secured in place by the bolt 14. An inside metal ring 15 and bolts 16 serve to make a secure connection between the flange 13 and the wooden rings 17 at each end of the rotor. Theinner end of the outside continuation 18 of the hollow perforated shaft 12 at each end of the rotor is threaded into the flange 13 and is further secured in place by the setscrew 19. The hollow pipes 18 are not perforated, but they are in proper alignment with the hollow perforated pipe 12. The hollow pipes 18 pass out through the stuffing boxes at each end of the cell and serve as the supporting shaft for the rotor. The bearings outside the cell in which the hollow pipes 18 rest and turn are not shown, nor are other outside parts here illustrated. When it is desired to remove the rotor, it is only necessary to loosen the setscrew 19 at each end of the rotor and to unscrew the hollow pipes 18 sufficiently far to permit the lifting out of the rotor. In the form of construction here shown, the longitudinal slats or strips 20 imparting a cylindrical shape to the rotor are held'in place by the end rings 17 and by the intermediate Supporting ring 21 which is perforated by holes 22. Around the cylinder outlined by the slats 20 is wrapped a layer of suitable screen 23. One or more layers of canvas 24 or other porous material is then wrapped around the rotor, and over this is placed a layer of screen 25. A re-entrant slot is formed along the entire length of the rotor by means of the two strips shown at 26, and the filler piece 27. An annular channel 28 is also formed entirely around each end of the rotor between the flange 13 and a part of the ring 17 by the cutting away of the portion of 17. The canvas wrapping 24 is purposely made longer and wider than necessary to just cover the dimensions of the rotor and is held securely in place by the rope 29 which is placed over the canvas 24 coverin and wedged down into the annular end channels 28 andinto the longitudinal slot formed by the strips 26. The longitudinal vanes or sweeps 30, extending the full length of the rotor, are placed outside of the screen g and are held in position by suitable connecting straps 31 and bolts .32. These vanes are shown only in Fig. 6. One of these vanes is made somewhat deeper than the others and is forced down into the longitudinal slot formed by the strips 26. The outer screen 25 has its side edges somewhat overlapped just above this slot and such edges are also forced into this slot by the particular longitudinal vane just H1811- tioned, and are thus secured in place.

In Figs. 1 and 2 the means for the introduction of air under pressure at both ends of the rotor is indicated at 33. The introduction of air is controlled by valves 34:. The rotor is driven by means of the pulley 35. The speed at which this rotor turns can be varied within Wide limits. but it is preferable that it move rather slowly in order to economizepowerv Five to thirty revolutions. per minute have been found suitable. The hollow pipes 18 pass through stuffing boxes 36 located near the lower part of the two ends of the cell and are supported by bearings 37. Suitable appliances or fittings, such as the stufiing box air head connection illustrated at 38 are provided for the proper connection of the hollow shaft of the rotor to the initial supply of air.

The air passing through the hollow shaft enters the rotor or drum proper through the perforations of the shaft and thence escapes quite uniformly through the porous covering of the rotor. This lssuing air entering the surrounding ore pulp thoroughly aerates the pulp, forming multitudes ofsmall air bubbles, which rise to the surface of the pulp and form columns of bubbles thereon. Concentration takes place therein and the mineral froth overflows the lip? and 8 into the launders 6, Figs. 3 and l.

While the apparatus illustrated anddescribed has been found particularly advantageous, yet it will be understood that variations and modifications may be made therein 7 without departing from the spirit of this invention. For instance, the rotor may have a polygonal cross section instead of circular,

or it may have sloping or conical sides as referred to the turning axis. Thevanes attached to the rotor maybe of other shapes than those shown in the drawing. It may be advantageous to so place them that there will be a constant tendency to gradually move the adjacent pulp material toward one end of the machine. The turning of the rotor need not be continuously in one direction but may, by suitable arrangement,turn any desired distance in one direction and then turn a desired dist-ancein the other.

much impairedthereby. Also in such machines, considerable punching or scraping of tie porous media must frequently'be resorted to with the consequent increase in labor costs and rapid deterioration or destruction of the porous medium.- Through the use of this invention theseundesirable features are eliminated. The described movement of the rotor, even when turnlng slowly, prevents the settling of the heavy particles on the pogested with porous media which move in a substantially horizontal plane. The apparatus of this invention is different from the above in that the porous medium of the 1'0- tor or drum rotates about: its longitudinal axis. The desired freedomfrom settling particles must be materially greater in the apparatus of this invention than in those wherein the porous medium moves in a horizontal plane, for the reasonthat any particle settling on'thetop surface of the rotor can scarcely fail to be removed when this top surface has been moved by rotation to the bottom position.

Another advantageof the apparatus of this invention is that of having the bottom of the enclosing cell so sl'iaped, and theair distributing rotor so placed therein, that before any particle can sink to the bottomof the machine and pass out with the tailing, it must come within the immediate and effective operating range of the issuing air and 1. An apparatus for the concentration of ores or other material by flotation, comprising a cell adapted to retain a body of pulp and having means of froth discharge; a rotor composed in part of finely porous material Within said cell; means for turning said rotor about a substantially horizontal axis, and means for passing a gas into said rotor and for its subsequent issuance through the porous material.

2. An apparatus for the concentration of ores or other material by flotation, comprising a cell adapted to retain a body of pulp and having means of froth discharge; a rotor composed in part of finely porous material in said cell, and in proximity to the bottom thereof, said cell having its bottom so shaped as to conform substantially to the size and shape of said rotor; means for turn ing said rotor about a substantially horizontal axis and means for passing a gas into said rotor and for its issuance through the porous material.

3. An apparatus for the concentration of ores or other material by flotation, com prising a cell adapted to retain a body of pulp and having means of froth discharge; an air distributing rotor composed in part of finely porous material Within said cell and in proximity to the bottom thereof, said cell having its bottom so shaped as to conform substantially to the size and shape of said rotor; means for turning said rotor about its axis; and means for passing air into said rotor and for its subsequent issuance through the Whole periphery of the porous material, so that for an appreciable period all particles of pulp come Within the effective range of the issuing air.

4. In a flotation apparatus for containing a body of pulp, means of froth discharge, an air distributing rotor adapted to fit in the separating cell, said rotor being composed in part of finely porous material: means for passing air into said rotor and for its subsequent issuance through the Whole p riphery of the porous material; and means for turning the said rotor about a substan-- tially horizontal axis, so that said porous material is cleansed Whilst the air is passing tl'ierethrough.

5. In a flotation apparatus for containing a body of pulp, means of froth discharge, a rotor mounted Within said apparatus and having at least a part of its cylindrical sur face formed of a finely porous medium, means for turning said rotor about a sub st-antially horizontal axis, and means cooperating With said rotor for permitting the passage of gas through said porous medium into said apparatus, said rotor being adapted While rotating to permit the uniform distribution of finely disseminated gas throughout substantially the entire area of the apparatus near the bottom thereof.

6. In a flotation apparatus for containing a body of pulp, means of froth discharge, a cylindrical rotor mounted Within said apparatus and having at least a part of its cylindrical surface formed of a finely porous medium, means for turning said rotor about a substantially horizontal axis, and means cooperating With said rotor for permitting the passage of gas through said porous medium into said apparatus.

7. In a flotation apparatus for containing a body of pulp, means of froth discharge, a hollow cylindrical rotor mounted Within said apparatus and having at least a part of its cylindrical surface formed of a finely porous medium, means for turning said rotor about a substantially horizontal axis, and means for introducing a gas into the interior of said rotor.

8. In a flotation apparatus for containing body of pulp, means of froth discharge, a hollow cylindrical rotor mounted Within said apparatus and having at least a part of its cylindrical surface formed of a finely porous medium, means for turning said rotor about a substantially horizontal axis, and means cooperating with said rotor for permitting the passage through said porous medium into said apparatus of finely disseminated gas uniformly distributed throughout substantially the entire area of the apparatus near the bottom thereof.

In testimony whereof, I have signed my name to this specification this 30th day of October, 1925.

JOHN G. MAoINTOSH. 

